Our objective is to demonstrate that nightmares in rape victims with post- traumatic stress disorder (PTSD) can be reduced with direct behavioral methods, and that such reductions in nightmares will improve sleep quality and decrease daytime distress. Traditionally, nightmares have been viewed as a symptom of an underlying psychological conflict which might only be treated with psychotherapy. Alternatively, several case reports have demonstrated efficacy with behavioral approaches to nightmares. Overall, however, research on the treatment of nightmares has been largely neglected. In our previous controlled studies, using an imagery rehearsal method in the treatment of chronic nightmare sufferers, we have observed significant reductions in nightmares, and improvements in sleep quality and daytime distress. Sustained reductions in nightmares as well as improvements in sleep and distress have also been demonstrated in long term followup studies. This research supports the theory that nightmares may function as an independent sleep disorder which contributes to sleep disturbance and daytime distress. These findings also raise the possibility that nightmares may interact bidirectionally with post-traumatic stress disorder. The proposed study will focus treatment directly on nightmares, often the most predominant intrusive symptom in PTSD. We will employ imagery rehearsal to directly treat nightmares in rape victims with PTSD. Imagery rehearsal involves three steps: recalling a nightmare; changing the nightmare in some manner; then rehearsing the new set of images from the changed version. This is performed in the waking state for several minutes each day. The study will use a randomized, controlled, non-blinded, clinical intervention, repeated measures design. Statistical analysis will be conducted with MANOVA in evaluating the effects of the behavioral treatment of nightmares on nightmare frequency, sleep quality and daytime distress in treatment vs. wait-list control groups. Within and between subjects analysis will be conducted at followup of six months. The study population will include adult female rape victims with PTSD who are at least three months post-assault and who suffer from nightmares at a minimum of once per week. The high prevalence of disturbing dreams and post traumatic symptoms make this population well suited for studying the treatment of nightmares in PTSD. A short term therapy with a positive impact on PTSD (including long-term improvement in sleep quality and daytime distress) will be at a premium as health care services undergo major changes. With the followup difficulties observed in victims of sexual assault and abuse, a short term approach, such as imagery rehearsal, may have special appeal to rape victims who suffer nightmares. If similar results to our earlier research were achieved, imagery rehearsal (though not curative) could prove to be a cost- effective adjunctive treatment.